Web Soil Survey

This past week, I got to use the USDA's Web Soil Survey online tool (here) for the first time - and it was pretty incredible. With this tool, you're able to look at most of the U.S. soil data, which includes soil types and a whole host of attributes of those soil types. What you can do with this information - sometimes manually, sometimes automatically - is determine quality of soil for your attempted use.

To keep this post a little shorter, I first recommend watching this quick video on how to use WSS (there were a few others on YouTube, but this seemed like the easiest to sit through): here.

So, basically, the user creates an Area of Interest, and can then choose from a host of data to display. I chose to use one of the more automatic tools and look at soil suitability for trails (Soil Data Explorer > Suitabilities and Limitations Ratings > Recreational Development > Paths and Trails). This brings up a color-coded soil map. Now, viewing the description of the rating shows that their paradigm assumes that trails "should require little or no slope modification through cutting and filling." Filling, yes; cutting, not so much. (Actually, the most sustainable trails according to the International Mountain Bike Association (IMBA) are cut into a hillside in such a way that allows water to sheet-flow off the trail. Where trails run into the most difficulty shedding water is when they are at grade, because compaction will quickly move them below grade.) However, some of the other data used to give the rating (stoniness, depth to water table, etc.) are very useful and appropriate.

I also found my way fairly quickly around some other key points, such as depth to water table alone, and water storage capacity. In the latter, the user sets depth to evaluate (surface to about 4 inches is what I ran) and the data returns with capacity of the soil to hold water, which is based off organic composition and other factors. It does not indicate how much water the soil might actually hold, only how much it could hold.

Why look at all this? Because, as I focus for the moment on a person's ability to go out and view the biodiversity at Raccoon Creek State Park, trail conditions are critical - very few casual hikers care to get their shoes and feet muddy and wet, or risk slipping and falling on adverse trails. And, unfortunately, some of the trails I'm familiar with in the park are not in great shape. The park is working to correct these issues, but I'm curious to discover if I can use soil data to plan trail corridors in the future to avoid troublesome areas - or at least be aware that more work might be needed to build a sustainable trail than simple marking it out and packing it down.

My initial impressions are the Web Soil Survey tool will help tremendously.